Economic growth on the whole is exponential, that's why it's expressed as percentage growth.

The rest of technology looks like many separate curves, which do tend to show exponential or logistic shapes, at least for long periods, from agriculture yields to coal plant efficiency, to solar. Economies do that too: the norm is exponential growth, n% multiplicative increase per year, rather than linear growth. There are shifts, e.g. the fast exponential for top speeds in aerospace ended once we got into space, while DNA sequencing just increased its growth rate several fold, but it's common for annual change to be multiplicative rather than additive.

Check out the Performance Curve Database for many individual improvement curves.